Erecting Suspended Powered Scaffolds Safe Work Method Statement

Installing suspended powered scaffolds requires specialist competencies beyond general scaffolding or rigging qualifications due to complex engineering, rigging, and safety system requirements. While no specific High Risk Work licence exists exclusively for suspended scaffold installation in Australia, installers should hold scaffolding High Risk Work licence (basic or intermediate class depending on complexity) demonstrating foundational scaffold knowledge, rigging or dogging licence for lifting beam and counterweight installation operations, and electrical licence (for licensed electrician conducting electrical system installation). Beyond licensing, installers require manufacturer-specific training for the particular suspended scaffold system being installed, as proprietary systems have unique components, assembly sequences, and safety features differing between manufacturers. Training should cover outrigger beam installation and anchoring procedures, counterweight calculation and installation, suspension rope rigging including termination installation and tensioning, platform assembly and component installation, electrical system installation and commissioning (for electricians), safety system installation and functional testing, load testing procedures and acceptance criteria, and inspection protocols per AS 1418.17. Engineering support from registered professional engineer is mandatory for design certification and final commissioning inspection—installers cannot self-certify installations regardless of experience. Some suspended scaffold manufacturers and suppliers provide installer certification programs documenting competency in their specific systems. Suspended scaffold installation work should be supervised by competent person with demonstrated suspended scaffold installation experience, adequate understanding of engineering principles governing suspended scaffold design and operation, and authority to stop work if installation deficiencies are identified. Workers conducting roof edge work during installation must hold Working at Heights training certification covering fall protection systems, harness use, and rescue procedures. Electrical installation must be conducted by licensed electrician holding appropriate electrical worker licence class for work being undertaken. First aid training is valuable for installation crews working at remote rooftop locations where emergency medical response may be delayed. Maintain training records documenting all installer qualifications, manufacturer training completion, and competency assessments. Refresher training should be provided when new equipment is introduced, when incidents identify knowledge gaps, or when regulatory requirements change.

Counterweight calculation for suspended scaffold outrigger beams requires structural engineering analysis balancing overturning moments from suspended platform loads against stabilising moments from counterweights, achieving minimum 4:1 stability ratio per AS 1418.17 requirements. Basic calculation methodology involves determining maximum platform overturning moment by multiplying maximum working load (including platform self-weight, workers, materials, and dynamic loads) by horizontal distance from building edge to platform centre of gravity, calculating counterweight stabilising moment by multiplying counterweight mass by horizontal distance from building edge to counterweight centre of gravity, and verifying ratio of stabilising moment to overturning moment exceeds 4:1 minimum safety factor. For example, if maximum platform load is 5000N (approximately 500kg) positioned 3 metres from building edge, overturning moment equals 5000N × 3m = 15,000Nm. If counterweight is positioned 1.5 metres behind building edge, required counterweight force to achieve 4:1 ratio equals (15,000Nm × 4) ÷ 1.5m = 40,000N, approximately 4000kg counterweight mass. Actual calculations must account for additional factors including outrigger beam self-weight which contributes to either overturning or stabilising moment depending on beam geometry and load distribution, dynamic amplification factors accounting for platform movement and material handling impacts, wind loads on suspended platforms creating additional overturning moments, and structural deflection of beams under load affecting moment arm distances. Calculations become more complex for multi-point suspension systems with multiple platforms or non-standard beam geometries. Australian Standard AS 1418.17 specifies detailed calculation methodologies and load factors that must be applied. Critical point often misunderstood is that stability ratio must be maintained under worst-case loading conditions not just typical loads—if platform will occasionally carry concentrated material loads or additional workers, counterweights must be adequate for maximum credible loads not average loads. Never reduce counterweights below engineering specifications attempting to reduce roof loading, as even small counterweight reductions can dramatically reduce stability margin potentially causing beam tipping under normal operational loads. Counterweight calculations must be conducted by registered professional engineer with structural engineering competency—contractors cannot self-calculate counterweights even if calculation methodology appears straightforward, as errors cause catastrophic failures. Engineer certification must specify exact counterweight quantities and positions, accounting for specific beam dimensions, suspension point locations, and platform configurations. If operational requirements change requiring heavier platform loads or different platform positions, counterweight recalculation by engineer is mandatory—do not exceed original design loads without engineering reassessment.

Suspension rope replacement criteria specified in AS 1418.1 and AS 1418.17 establish maximum acceptable deterioration levels beyond which ropes must be removed from service to prevent failures. Primary inspection criteria include broken wire counts where ropes showing more than 10% of total wire breaks within any rope lay length, or more than 5 broken wires in any strand within one lay length, must be replaced immediately. For context, 6×19 rope construction common in suspended scaffolds has approximately 114 wires total, so 10% equals roughly 11 broken wires along any lay length section. Diameter reduction exceeding 7% from nominal rope diameter requires rope replacement—measure diameter at multiple locations using micrometer comparing to nominal specification, replacing ropes if any measurement shows more than 7% reduction. For 10mm nominal diameter rope, 7% reduction means replacement at 9.3mm measured diameter. Corrosion assessment requires replacement if ropes show corrosion causing pitting reducing wire diameters, internal corrosion evidenced by broken wires at strand valleys, or general corrosion causing significant rope diameter reduction. Other replacement criteria include kinking where rope has permanent deformation from being bent beyond elastic limit, bird caging where outer strands have separated from rope core creating basket appearance, heat damage evidenced by wire discolouration or fused wires, mechanical damage including flattening or crushing, rope rotation causing unlaying of outer strands, and worn or damaged terminations where wire rope grips show slippage, deformation, or inadequate grip counts. Critical understanding is that these are maximum acceptable deterioration levels—best practice replaces ropes before deterioration reaches replacement criteria. Suspension ropes in harsh environments including coastal locations with salt exposure, industrial areas with chemical contamination, or tropical climates with high humidity should be replaced more frequently than minimum criteria would indicate. Visual inspection alone is inadequate for detecting internal rope deterioration—ropes may appear serviceable externally whilst internal wires are corroded or broken. Some inspection techniques including magnetic particle inspection or ultrasonic testing can detect internal deterioration but these are specialist procedures rarely used on construction suspended scaffolds. Practical approach is implementing rope replacement schedules based on service duration and inspection condition rather than waiting until deterioration reaches maximum criteria. For suspended scaffolds in continuous use, annual rope replacement regardless of apparent condition provides margin for unexpected deterioration. For systems seeing only occasional use, inspection-based replacement is acceptable but inspections must be thorough and documented. Never extend rope service life beyond manufacturer recommendations or engineering specifications attempting to reduce replacement costs—rope replacement is inexpensive compared to consequences of rope failures.

Suspended scaffold emergency procedures must address rope failure scenarios ensuring worker survival and safe platform recovery if primary suspension systems fail. AS 1418.17 mandates secondary suspension rope systems providing redundant support independent of primary ropes—if primary rope breaks, secondary rope automatically engages preventing platform fall. Secondary rope systems use similar wire ropes to primary suspension but with independent suspension from outrigger beams, automatic engaging mechanisms including shock absorbers that activate if primary rope load is suddenly transferred, and adequate capacity to support full platform load after primary rope failure. Beyond secondary suspension, emergency procedures require workers to wear full-body fall arrest harnesses throughout suspended scaffold operations with harness lanyards connected to independent anchor points on platform or building structure. If rope failure causes platform tipping or catastrophic drop despite secondary suspension, harnesses arrest worker falls preventing multi-storey falls. Emergency descent systems including manual descent devices or battery-powered emergency lowering mechanisms allow controlled lowering of platform to ground if primary power fails or hoists become inoperative. Operators must be trained in emergency descent procedures including activating emergency systems, controlling descent rate, and landing platform safely without striking ground or building structure. Communication protocols ensure ground personnel are aware of emergency situations and can provide assistance including summoning emergency services, implementing rescue procedures for workers suspended in harness arrest after falls, and securing ground area preventing bystanders approaching beneath disabled suspended platform. Emergency procedures must address multiple failure scenarios including single rope failure with secondary rope engaging and platform remaining usable allowing normal descent, double rope failure requiring immediate harness arrest and rescue of suspended workers, hoist motor failure requiring emergency manual lowering, power failure requiring battery backup or manual emergency descent, and rope jamming or brake failure requiring alternative descent methods. Regular emergency drills should be conducted where workers practice emergency descent procedures, harness use, and rescue responses ensuring they can implement procedures instinctively under stress. Emergency equipment including spare ropes, manual descent devices, rescue harnesses, and communication devices must be immediately accessible at suspended scaffold work locations—equipment stored remotely is ineffective in actual emergencies requiring immediate response. Ground-based rescue teams must be designated and equipped including personnel trained in rope rescue techniques, descent devices, and first aid, immediately available throughout suspended scaffold operations. Emergency service notification procedures must include building address, suspended scaffold location on building, height above ground, number of workers involved, and nature of emergency, pre-prepared on cards or signs allowing rapid accurate communication under stress. Critical understanding is that suspended scaffold emergencies require immediate response within minutes—delayed rescue of workers suspended in harnesses leads to suspension trauma, unconsciousness, and death even if workers were uninjured by original rope failure.

Ongoing inspection and maintenance requirements for suspended scaffolds throughout their service life ensure continued structural integrity and operational safety. AS 1418.17 specifies inspection frequency and scope at multiple intervals. Daily pre-use inspections conducted by scaffold operators before each work shift must check suspension ropes for visible broken wires, corrosion, kinks, or damage, verify rope terminations show no slippage or deformation, inspect platform components including guardrails, toe boards, and deck planking for damage or missing components, test hoist motor operation including raising, lowering, and braking functions, activate emergency stop and safety devices verifying they function correctly, verify harness anchor points on platform are secure and undamaged, and document inspection on written checklist. If daily inspection identifies any deficiencies, scaffold must not be used until defects are corrected and re-inspected. Weekly detailed inspections by competent person with suspended scaffold knowledge verify structural integrity of outrigger beams checking for corrosion, weld cracks, or permanent deformation, measure suspension rope diameters at multiple locations documenting any diameter reduction trends, count broken wires along full rope lengths comparing to replacement criteria, inspect counterweights verifying adequate quantities remain installed and securing systems are intact, test electrical systems including RCD function and earthing continuity, load test hoists and brakes applying loads verifying adequate capacity, inspect platform structural components including welds and connections, and document findings in scaffold register. Three-month periodic inspections require more comprehensive assessment including engineering review verifying continued compliance with design specifications, rope non-destructive testing if available detecting internal deterioration, load testing of hoists and structural components verifying capacity maintenance, review of maintenance records identifying wear patterns or recurring defects, and re-certification by professional engineer if significant repairs or modifications have occurred. Annual major inspections should include complete disassembly and inspection of all components, rope replacement regardless of apparent condition providing fresh ropes for next service year, hoist motor servicing including gearbox oil changes and brake pad replacement, electrical system testing and certification, structural beam inspection including non-destructive testing of critical welds, counterweight verification and replacement of deteriorated blocks, and comprehensive load testing re-verifying structural capacity. Maintenance activities between inspections include lubricating ropes per manufacturer recommendations using appropriate wire rope lubricants preventing corrosion, greasing hoist gearboxes and brake mechanisms, tightening structural fasteners showing looseness, replacing worn platform components including damaged guardrails or planking, repairing electrical systems addressing insulation damage or connection deterioration, and touching up protective coatings on steel components preventing corrosion progression. Critical importance is documenting all inspections and maintenance in scaffold register—undocumented maintenance is effectively no maintenance from regulatory compliance perspective. Scaffold registers should travel with equipment maintaining complete service history regardless of ownership changes or equipment relocations. Never extend inspection intervals beyond specified frequencies attempting to reduce costs—inspection scheduling is based on deterioration rates and failure consequence, not convenience. If suspended scaffold is idle for extended periods, conduct full inspection before returning to service regardless of time since last inspection, as deterioration can progress during storage particularly in unprotected outdoor conditions.